I have ridden bikes from the dealership all the way from Sportster 883 to the Ultra Classic. Guess its a perk, lol. Anyway, some have had regular Harley oil and to me and IMO they have run hotter, and have the noise in the tranny, especially in 07. I asked Bob's Harley-Davidson, where I worked at the time to put it in all three cavities based on what I had noticed and just from talking to people and getting opinions from everyone. I gave it a shot and have been happy since.
Oops, part left out.
I am not opposed to switching to a different oil at all. Mobil1, Spectro, any of them. I was just voicing my opinion on the Syn3 oils as well.